change the UX around project creation

[devoncarew]

When we create a new flutter project, the flutter create scrolls by, then gets replaced by the Dart Analysis view. Instead, we may want to do something like:

• show flutter create progress in a progress job (we shouldn't open a message panel at all; it fights with the analysis view)
• show a toast when the project create is finished

[mit-mit]

Could we do the flutter create step as a new last page (displaying the output we currently print to the message panel) in the New Project wizard? I find it a little odd that we do so much work after the wizard has closed (leading to a long time after the wizard until the developer can actually start coding).

[mit-mit]

While we are at it, can we also reconsider the first page in the wizard that asks for the SDK path every time I create project?

[devoncarew]

+1 to both of those ideas!

[devoncarew]

Closing as we've done some work here, and have other issues tracking this as.